# NTSB LAX97LA030: Bell 206B, N90144, Supai, AZ, November 1, 1996 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: November 1, 1996, 12:30 local (19:30 UTC) - Place: Supai, AZ - Coordinates: 35.639514, -113.610397 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.6395&lon=-113.6104&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report August 21, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 29675 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX97LA030 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29675/pdf - Page: https://openairdocs.org/ntsb/LAX97LA030 ## Probable cause improper routing of the external cargo hoist cable (over helicopter skid), which resulted in lateral imbalance and roll-over of the helicopter, as weight on the cable became effective. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - in flight, hover - external load equipment - improper (cause) - aircraft weight and balance - uncontrolled (cause) - remedial action - not attained (cause) - aircraft control - not possible - load jettison - Roll over, hover - dynamic rollover - In flight collision with terrain/water, descent - uncontrolled ## Analysis The helicopter was was being used in an external lift operation, moving supplies of salt to a storage location. The pilot reported that he was lifting to a hover over a loaded cargo net, unaware that the external load cable was draped over one of the skids. As the cable took the strain of the load, the helicopter rolled, and the lateral control limit was exceeded. The pilot released the load with an electrical switch; however, before control was regained, the helicopter contacted the ground, nose low, and the main rotor blades struck the ground. The pilot reported that from initial down-force on the skid until impact, the time frame was less than 4 seconds. He also reported no mechanical malfunction with the helicopter. ## Factual narrative On November 1, 1996, at 1230 hours mountain standard time, a Bell 206B helicopter, N90144, dynamically rolled over and crashed while lifting an external sling load from an uncharted mountainous helipad located near Supai, Arizona. The helicopter was owned and operated by Action Helo of Arizona, under 14 CFR Part 133 for the local flight. Visual meteorological conditions prevailed at the time of the accident and a company VFR flight plan had been filed for the operation. The helicopter was destroyed and property on the ground was damaged in the ensuing crash. The certificated commercial pilot, the sole occupant, sustained minor injuries. In his written accident report, the pilot said that "while lifting to a hover over a cargo net external load, the 40 foot cable became fouled over the skid (left-right unknown). Control limits were exceeded with an increasing roll rate. The load was released by the electrical switch but the helicopter contacted the ground nose low striking main rotors to the ground. From initial down-force on [the] skid to impact[, it] was less than perhaps four seconds." The pilot also reported that there were no mechanical malfunctions with the helicopter. ## Aircraft - Registration: [N90144](https://openairdocs.org/deregistered/N90144-2017-03-21), registration cancelled 2017-03-21, S/N 1623, built 1975 (OpenAirDocs) - Reported make and model: Bell 206B - Registry model: [Bell 206B](https://openairdocs.org/model/bell-206b) (registry code 1181511) (OpenAirDocs) - Registry engine: [Allison 250 SER 400HP](https://openairdocs.org/engine/allison-250-ser-400hp) (registry code 03013, turbo-shaft) (OpenAirDocs) - Category: Helicopter - Serial number: 1623 - Engines: Allison 250-C20B 425 horsepower turbo shaft - Damage: Destroyed - Flight: Part 133 - Registered owner: Donald A. Parrish - Airworthiness certificate: Standard, Normal - Last inspection: Annual, October 31, 1996, 3 hours before - Flight plan: Company VFR - Airport: Uncharted Heliport ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane, helicopter; medical: class 2, valid medical--w/ waivers/lim; seat: right; flight hours: 9,970 total, 4,150 in this make and model, 9,317 as pilot in command, 112 in the last 90 days, 35 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 50 °F ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19961101034759A](https://openairdocs.org/incident/19961101034759A), Nov 1, 1996: Bell 206B, Supai, AZ, Destroyed. Helicopter lifted off helipad with an external load when cable became entangled in landing skid. Rolled over. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.